Incidentally, it's the same in Ruby, and supports : a = [1,2,3] => [1, 2, 3] a << a => [1, 2, 3, [...]] a.inspect It's not true laziness, though; i

Incidentally, it's the same in Ruby, and supports : a = [1,2,3] => [1, 2, 3] a << a => [1, 2, 3, [...]] a.inspect It's not true laziness, though; it's as long as the list when you tie it to itself.